Method and system for applying electric fields to multiple solar panels

ABSTRACT

A solar cell management system for increasing the efficiency and power output of a solar cell and methods for making and using the same. The management system provides an electric field across one or more solar cells. The imposed electric field exerts a force on both the electrons and holes created by light incident on the solar cell and accelerates the electron-hole pairs towards the electrodes of the solar cell. The solar cell management system considers variations in configuration of solar cells to maximize the power output of the solar cells. The accelerated electron-hole pairs have a lower likelihood of recombining within the cells&#39; semiconductor&#39;s material. This reduction in the electron-hole recombination rate results in an overall increase in the solar cells&#39; efficiency and greater power output.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of co-pending U.S. patentapplication Ser. No. 15/410,657, filed on Jan. 19, 2017, which is adivisional application of co-pending U.S. patent application Ser. No.14/637,353, filed on Mar. 3, 2015, now U.S. Pat. No. 10,103,547, whichis a continuation-in-part of, and claims the benefit of, U.S. patentapplication Ser. No. 14/628,079, filed Feb. 20, 2015, now U.S. Pat. No.10,069,306, which claims the benefit of U.S. Provisional ApplicationSer. No. 61/943,127, filed Feb. 21, 2014; U.S. Provisional ApplicationSer. No. 61/943,134, filed Feb. 21, 2014; U.S. Provisional ApplicationSer. No. 61/947,326, filed Mar. 3, 2014; and U.S. ProvisionalApplication Ser. No. 62/022,087, filed Jul. 8, 2014, the disclosures ofwhich are hereby incorporated by reference in their entireties and forall purposes.

FIELD

The present disclosure relates generally to photovoltaic devices andmore specifically, but not exclusively, to systems and methods formaximizing the power or energy generated and the overall efficiency ofone or more solar cells, for example, by applying and adjusting anexternal electric field across the solar cells.

BACKGROUND

A solar cell (also called a photovoltaic cell) is an electrical devicethat converts the energy of light directly into electricity by a processknown as “the photovoltaic effect.” When exposed to light, the solarcell can generate and support an electric current without being attachedto any external voltage source.

The most common solar cell consists of a p-n junction 110 fabricatedfrom semiconductor materials (e.g., silicon), such as in a solar cell100 shown in FIG. 1. For example, the p-n junction 110 includes a thinwafer consisting of an ultra-thin layer of n-type silicon on top of athicker layer of p-type silicon. Where these two layers are in contact,an electrical field (not shown) is created near the top surface of thesolar cell 100, and a diffusion of electrons occurs from the region ofhigh electron concentration (the n-type side of the p-n junction 110)into the region of low electron concentration (the p-type side of thep-n junction 110).

The p-n junction 110 is encapsulated between two conductive electrodes101 a, 101 b. The top electrode 101 a is either transparent to incident(solar) radiation or does not entirely cover the top of the solar cell100. The electrodes 101 a, 101 b can serve as ohmic metal-semiconductorcontacts that are connected to an external load 30 that is coupled inseries. Although shown as resistive only, the load 30 can also includeboth resistive and reactive components.

When a photon hits the solar cell 100, the photon either: passesstraight through the solar cell material—which generally happens forlower energy photons; reflects off the surface of the solar cell; orpreferably is absorbed by the solar cell material—if the photon energyis higher than the silicon band gap—generating an electron-hole pair.

If the photon is absorbed, its energy is given to an electron in thesolar cell material. Usually this electron is in the valence band and istightly bound in covalent bonds between neighboring atoms, and henceunable to move far. The energy given to the electron by the photon“excites” the electron into the conduction band, where it is free tomove around within the solar cell 100. The covalent bond that theelectron was previously a part of now has one fewer electron—this isknown as a hole. The presence of a missing covalent bond allows thebonded electrons of neighboring atoms to move into the hole, leavinganother hole behind. In this way, a hole also can move effectivelythrough the solar cell 100. Thus, photons absorbed in the solar cell 100create mobile electron-hole pairs.

The mobile electron—hole pair diffuses or drifts toward the electrodes101 a, 101 b. Typically, the electron diffuses/drifts towards thenegative electrode, and the hole diffuses/drifts towards the positiveelectrode. Diffusion of carriers (e.g., electrons) is due to randomthermal motion until the carrier is captured by electrical fields.Drifting of carriers is driven by electric fields established across anactive field of the solar cell 100. In thin film solar cells, thedominant mode of charge carrier separation is drifting, driven by theelectrostatic field of the p-n junction 110 extending throughout thethickness of the thin film solar cell. However, for thicker solar cellshaving virtually no electric field in the active region, the dominantmode of charge carrier separation is diffusion. The diffusion length ofminor carriers (i.e., the length that photo-generated carriers cantravel before they recombine) must be large in thicker solar cells.

Ultimately, electrons that are created on the n-type side of the p-njunction 110, “collected” by the p-n junction 110, and swept onto then-type side can provide power to the external load 30 (via the electrode101 a) and return to the p-type side (via the electrode 101 b) of thesolar cell 100. Once returning to the p-type side, the electron canrecombine with a hole that was either created as an electron-hole pairon the p-type side or swept across the p-n junction 110 from the n-typeside.

As shown in FIG. 1, the electron-hole pair travels a circuitous routefrom the point the electron-hole pair is created to the point where theelectron-hole pair is collected at the electrodes 101 a, 101 b. Sincethe path traveled by the electron-hole pair is long, ample opportunityexists for the electron or hole to recombine with another hole orelectron, which recombination results in a loss of current to anyexternal load 30. Stated in another way, when an electron-hole pair iscreated, one of the carriers may reach the p-n junction 110 (a collectedcarrier) and contribute to the current produced by the solar cell 100.Alternatively, the carrier can recombine with no net contribution tocell current. Charge recombination causes a drop in quantum efficiency(i.e., the percentage of photons that are converted to electric currentwhen the solar cell 100), and, therefore, the overall efficiency of thesolar cell 100.

Recent attempts to reduce the cost and increase the efficiency of solarcells include testing various materials and different fabricationtechniques used for the solar cells. Another approach attempts toenhance the depletion region formed around the p-n junction 110 forenhancing the movement of charge carriers through the solar cell 100.For example, see U.S. Pat. No. 5,215,599, to Hingorani, et al.(“Hingorani”), filed on May 3, 1991, and U.S. Pat. No. 8,466,582, toFornage (“Fornage”), filed on Dec. 2, 2011, claiming priority to a Dec.3, 2010 filing date, the disclosures of which are hereby incorporated byreference in their entireties and for all purposes.

However, these conventional approaches for enhancing the movement ofcharge carriers through the solar cell 100 require a modification of thefundamental structure of the solar cell 100. Hingorani and Fornage, forexample, disclose applying an external electric field to the solar cellusing a modified solar cell structure. The application of the externalelectric field requires a voltage to be applied between electrodesinducing the electric field (described in further detail with referenceto equation 2, below). Without modifying the fundamental structure ofthe solar cell 100, applying the voltage to the existing electrodes 101a, 101 b of the solar cell 100 shorts the applied voltage through theexternal load 30. Stated in another way, applying voltage to theelectrodes 101 a, 101 b of the solar 100 is ineffective for creating anexternal electric field and enhancing the movement of charge carriers.Accordingly, conventional approaches—such as disclosed in Hingoriani andFornage—necessarily modify the fundamental structure of the solar cell100, such as by inserting an external (and electrically isolated) set ofelectrodes on the base of the solar cell 100. There are severaldisadvantages with this approach.

For example, the external electrodes must be placed on the solar cell100 during the fabrication process—it is virtually impossible toretrofit the external electrodes to an existing solar cell or panel.This modification to the fabrication process significantly increases thecost of manufacturing and decreases the manufacturing yield.Additionally, placement of the external electrodes over the front, orincident side, of the solar cell 100 reduces the optical energy whichreaches the solar cell 100, thereby yielding a lower power output.

As a further disadvantage, to yield significant improvements in poweroutput of the solar cell 100, sizeable voltages must be applied to theexternal electrodes of the solar cell 100. For example, Fornagediscloses that voltages on the order of “1,000's” of volts must beplaced on the external electrodes for the applied electric field to beeffective and increase the power output of the solar cell 100. Themagnitude of this voltage requires special training for servicing aswell as additional high voltage equipment and wiring that does notpresently exist in existing or new solar panel deployments. As anexample, an insulation layer between the external electrodes and thesolar cell 100 must be sufficient to withstand the high applied voltage.In the event of a failure of the insulation layer, there is asignificant risk of damage to not only the solar cell 100, but also allsolar cells 100 connected in series or parallel to the failed solar cellas well as the external load 30.

As a further disadvantage, typical installation of the solar cell 100can introduce additional factors—such as additional wiring, externalhardware, and so on—that can affect the power output of the solar cell100. For example, multiple solar cells 100 can be coupled (in seriesand/or parallel) together to form a solar panel 10 (shown in FIGS.2A-D). Each solar panel 10 can then be coupled using any suitable meansdescribed herein, including in parallel, series, or a combinationthereof. With reference to FIGS. 2A-D, typical installationconfigurations using at least one solar panel 10 are shown.

The solar panels 10 can be connected in either parallel (FIG. 2A),series (FIG. 2B), or a combination thereof (FIG. 2C). In each of FIGS.2A-C, the solar panels 10 can drive a load, such as an inverter 31. FIG.2A shows a series coupling of the solar panels 10. Turning to FIG. 2B,the solar panels 10 are shown connected in series and drives theinverter 31. FIG. 2C shows an alternative installation of the solarpanels 10 connected both in parallel and in series. In yet anotherembodiment, FIG. 2D shows an installation—typically found in manyresidential installations—where each of the solar panels 10 areconnected to its own inverter 31.

Each method of connecting the solar cells 100 and the solar panels 10requires different wiring and installation methods that change theelectrical characteristics/behavior, and the corresponding power output,of the connected solar panels 10. Conventional efforts to increase theefficiency of solar cells rarely account for installation obstacles,such as the various methods for connecting multiple solar cells 100and/or multiple solar panels 10.

In view of the foregoing, a need exists for an improved solar cellsystem and method for increased efficiency and power output, such aswith increased mobility of electron-hole pairs, in an effort to overcomethe aforementioned obstacles and deficiencies of conventional solar cellsystems.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplary top-level cross-sectional diagram illustrating anembodiment of a solar cell of the prior art.

FIG. 2A is an exemplary top-level block diagram illustrating oneembodiment of a solar panel array of the prior art using the solar cellsof FIG. 1.

FIG. 2B is an exemplary block diagram illustrating an alternativeembodiment of a solar panel array of the prior art using the solar cellsof FIG. 1, wherein each solar panel is coupled in series.

FIG. 2C is an exemplary block diagram illustrating an alternativeembodiment of a solar panel array of the prior art using the solar cellsof FIG. 1, wherein each solar panel is coupled both in series and inparallel.

FIG. 2D is an exemplary block diagram illustrating an alternativeembodiment of a solar panel array of the prior art using the solar cellsof FIG. 1, wherein each solar panel is directly coupled to a load.

FIG. 3 is an exemplary top-level block diagram illustrating anembodiment of a solar cell management system.

FIG. 4 is an exemplary block diagram illustrating an embodiment of thesolar cell management system of FIG. 3, wherein a solar panel array iswired in parallel according to the arrangement shown in FIG. 2A andcoupled to a voltage source through a switch.

FIG. 5 is an exemplary block diagram illustrating an alternativeembodiment of the solar cell management system of FIG. 3, wherein asolar panel array is wired in parallel according to the arrangementshown in FIG. 2A and coupled to a voltage pulser circuit.

FIG. 6 is an exemplary block diagram illustrating an alternativeembodiment of the solar cell management system of FIG. 4, wherein thesolar panel array is coupled in series according to the arrangementshown in FIG. 2B.

FIG. 7 is a graph illustrating an applied voltage V_(APP) relative tothe voltage across each solar panel of the solar cell management systemof FIG. 6.

FIG. 8 is an exemplary block diagram illustrating an alternativeembodiment of the solar cell management system of FIG. 6, wherein one ormore of the solar panel arrays are coupled to a voltage source throughone or more switches.

FIG. 9 is an exemplary block diagram illustrating another alternativeembodiment of the solar cell management system of FIG. 4, wherein one ormore of the solar panel arrays are coupled to the voltage source throughone or more switches.

FIG. 10 is an exemplary block diagram illustrating another alternativeembodiment of the solar cell management system of FIG. 4, wherein one ormore of the solar panel arrays are wired both in series and parallelaccording to the arrangement shown in FIG. 2D and are coupled to thevoltage source through a switch.

FIG. 11 is an exemplary block diagram illustrating another alternativeembodiment of the solar cell management system of FIG. 10, wherein oneor more of the solar panel arrays are coupled to the voltage sourcethrough one or more switches.

FIG. 12A-B are exemplary block diagrams illustrating alternativeembodiments of the solar cell management system of FIG. 4 cooperatingwith the solar panel array of FIG. 2E.

FIG. 13 is an exemplary block diagram illustrating an alternativeembodiment of the solar cell management system of FIG. 5, wherein thesolar panel array is wired in series according to the solar panel arrayof FIG. 2B.

FIG. 14 is a graph illustrating an applied voltage V_(APP) relative tothe voltage across each solar panel of the solar cell management systemof FIG. 13.

FIGS. 15A-B are exemplary block diagrams illustrating alternativeembodiments of the solar cell management system of FIG. 13, wherein oneor more of the solar panel arrays are coupled to one or more voltagepulsers.

FIG. 16 is an exemplary block diagram illustrating an alternativeembodiment of the solar cell management system of FIG. 5, wherein thesolar panel array is wired according to the arrangement shown in FIG.2C.

FIGS. 17A-B are exemplary block diagrams illustrating alternativeembodiments of the solar cell management system of FIG. 5, wherein thesolar panel array is wired according to the arrangement shown in FIG.2D.

FIG. 18 is an exemplary circuit diagram illustrating an embodiment of apulse uplift circuit for use with the solar cell management system ofFIG. 5.

It should be noted that the figures are not drawn to scale and thatelements of similar structures or functions are generally represented bylike reference numerals for illustrative purposes throughout thefigures. It also should be noted that the figures are only intended tofacilitate the description of the preferred embodiments. The figures donot illustrate every aspect of the described embodiments and do notlimit the scope of the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Since currently-available solar cell systems fail to maximize the poweroutput of a photovoltaic cell, a solar cell system that increases themobility of electron-hole pairs and reduces the recombination current ina semiconductor material can prove desirable and provide a basis for awide range of solar cell systems, such as to increase the efficiency andpower output of solar cells configured as a solar panel. This result canbe achieved, according to one embodiment disclosed herein, by a solarcell management system 300 as illustrated in FIG. 3.

Turning to FIG. 3, the solar cell management system 300 is suitable foruse with a wide range of photovoltaic devices. In one embodiment, thesolar cell management system 300 can be suitable for use with the solarcell 100 shown in FIG. 1. For example, the solar cell 100 can representany suitable generation of solar cells such as wafer-based cells ofcrystalline silicon (first generation), thin film solar cells includingamorphous silicon cells (second generation), and/or third generationcells. The solar cell management system 300 advantageously can be usedwith any generation of solar cell 100 without structuralmodification—and the associated drawbacks.

In another embodiment, the solar cell management system 300 can besuitable for use with multiple solar cells 100, such as the solar panels10 shown in FIGS. 2A-D. As previously discussed, multiple solar cells100 can be coupled (in series and/or parallel) together to form a solarpanel 10. The solar panels 10 can be mounted on a supporting structure(not shown) via ground mounting, roof mounting, solar tracking systems,fixed racks, and so on and can be utilized for both terrestrial andspace borne applications. Similarly, the solar cell management system300 advantageously can be used with any generation of solar panel 10without structural modification—and the associated drawbacks—of thesolar panel 10.

As shown in FIG. 3, the photovoltaic device 200 cooperates with anelectric field 250. In some embodiments, the polarity of the electricfield 250 can be applied in either the same direction or the reversedirection as the polarity of the electrodes 101 a, 101 b (shown inFIG. 1) in the photovoltaic device 200. For example, if applying theelectric field 250 in the same direction as the polarity of theelectrodes 101 a, 101 b in the photovoltaic device 200, the electricfield 250 acts on the electron-hole pairs in the photovoltaic device 200to impose a force—e⁻E or h⁺E on the electron or hole,respectively—thereby accelerating the mobility of the electron and holetowards respective electrodes. Alternatively, if the polarity of theelectric field 250 is reversed, the mobility of the electron-hole pairsin the photovoltaic device 200 decreases, thereby increasing therecombination current within the photovoltaic device 200. Accordingly,the efficiency of the photovoltaic device 200 can be diminished asdesired, such as for managing the power output of the photovoltaicdevice 200.

Furthermore, the electric field 250 applied to the photovoltaic device200 can be static or time varying as desired. In the case where theelectric field 250 is time varying, the electric field 250 has a timeaveraged magnitude that is non-zero. Stated in another way, the netforce on the electrons and holes is non-zero to provide increasedmobility in the electron-hole pairs of the photovoltaic device 200.

The solar cell management system 300 can apply the external voltageV_(App) to the photovoltaic device 200 using any suitable meansdescribed herein, including using a switch 55 as shown in FIG. 4.Turning to FIG. 4, the photovoltaic device 200 can represent any numberof photovoltaic devices such as the solar cell 100 and/or the solarpanels 10 as illustrated. The solar panels 10 are shown to be wired inparallel (also shown in FIG. 2A) and are connected to the switch 55,such as a single pole, double throw (or three-way) switch. However, aswill be discussed with reference to FIGS. 6 and 8-12, the solar panels10 also can be wired in series, a combination of series and parallel,and independently from one another. In one embodiment, the switch 55 isalso coupled to a voltage source 50 and an external load R_(L) (e.g.,shown as the inverter 31). The inverter 31 can include both resistiveand reactive components. In some embodiments, the inverter 31 canconvert a DC voltage and current into an AC voltage and current, whichis typically compatible in voltage and frequency with conventional ACpower grids. The output frequency of the inverter 31 and the amplitudeof the AC current/voltage can be based upon country, location, and localgrid requirements.

The voltage source 50 can include any suitable means for maintaining aconstant voltage, including ideal voltage sources, controlled voltagesources, and so on. However, in some embodiments, the voltage source 50can have a variable, adjustable output (e.g., time varying voltage). Aswitch control (or controller) 45 is coupled to the switch 55 to controlthe duration of connection and/or the frequency of switching, such asbetween the voltage source 50 and the inverter 31 to the solar panels10. The switch controller 45 can be preset to operate at a fixedswitching duration D and switching frequency f. In some embodiments, themagnitude of the voltage V_(App) applied by voltage source 50, theduration D of connection, and/or the frequency f of switching can bepreset and/or vary based on load conditions.

For example, the switch 55 connects the solar panels 10 with the voltagesource 50 in a first position (as shown with the arrow in the switch 55of FIG. 4). When connected in the first position, the voltage source 50applies the voltage V_(APP) across the electrodes 101 a, 101 b (shown inFIG. 1) of the solar panels 10 and induces the electric field 250 (shownin FIG. 3) across each solar panel 10. Once the electric field 250 hasbeen established across the solar panels 10, the switch 55 switches toconnect the solar panels 10 to the inverter 31 (i.e., the load R_(L)) ina second position. Accordingly, the voltage source 50 can provide theelectric field 250 without being connected to the solar panels 10 andthe inverter 31 at the same time. Therefore, applying the externalvoltage V_(APP) does not allow the load R_(L) (e.g., the inverter 31) todraw current directly from the voltage source 50.

Application of the electric field 250 to the solar panels 10 canincrease the current and power output of the solar panels 10 by apredetermined amount when the solar panels 10 subsequently are connectedto the inverter 31 in the second position. The predetermined amount isdependent upon an intensity of light incident on the solar panels 10,the voltage applied V_(APP) to the solar panels 10 by the voltage source50, the thickness of the solar panels 10, the frequency f that thevoltage source 50 is connected to the solar panels 10, and the dutycycle of the switching process between the first position and the secondposition—with the duty cycle being defined as the amount of time thatthe solar panels 10 are connected to the voltage source 50 divided by1/f the switching time (i.e., multiplied by the frequency f or dividedby the total period of the signal). It should be noted that the switchduration time D, the switching frequency f, and the duty cycle are allinterrelated quantities such that quantifying any two of the quantitiesallows for determination of the third quantity. For example, specifyingthe switching frequency and the duty cycle allows for determination ofthe switch duration time D. For example, under high intensity lightconditions, the improvement in power output can be on the order of 20%;under low light conditions, 50+%.

The embodiment shown in FIG. 4 advantageously provides the electricfield 250 to the photovoltaic device 200 without the need to modify thesolar panels 10 and/or solar cells 100 to include additional, externalelectrodes.

In some embodiments, an energy storage device—such as a capacitor 41, aninductor 42, and/or a battery 43—can be placed before the inverter 31 tomitigate any voltage drop-out being seen by the inverter 31 while theswitch 55 is in the first position. Accordingly, while the inverter 31(i.e., load) is disconnected from the solar panels 10 when the switch 55is in the first position and the electric field 250 is being establishedacross the solar panels 10, the energy storage device supplies energy tothe inverter 31 to keep current flowing during this switched period.Stated in another way, the energy storage device can discharge while thesolar panels 10 are disconnected from the inverter 31.

Therefore, a constant voltage from the voltage source 50—which in turncreates the electric field 250—need not be applied continuously to seean improvement in the power output of the solar panels 10. For example,with duration switching times D of nominally 10-2000 ns, V_(App)'s ofnominally 100-500+ Volts, and a switching frequency f of 20 μseconds,the duty cycle of nominally 0.1-10% can be used. The inductor 42, thecapacitor 41, and/or the battery 43 are chosen to be of sufficient sizeto provide enough discharge while the solar panels 10 are disconnectedwhile the electric field 250 is being placed across the solar panels 10so as not to cause a drop out on the output of the inverter 31.

FIG. 5 illustrates an alternative embodiment of the solar cellmanagement system 300 of FIG. 3. Turning to FIG. 5, the photovoltaicdevice 200 can represent any number of photovoltaic devices such as thesolar cell 100 and/or the solar panels 10 as illustrated. As shown, thesolar panels 10 are wired in parallel (also shown in FIG. 2A), but canalso be wired in series and any combination thereof as will be discussedwith reference to FIGS. 13 and 15-17.

A voltage pulser 60, such as a high voltage pulse generator, can apply atime varying voltage pulse across one or more of the solar panels 10. Inone embodiment, a duration D_(P) of the voltage pulse can beshort—nominally 10-2000 ns—and a magnitude can be high—nominally100-500+ Volts. In the embodiment shown in FIG. 5, the voltages applied,the pulse width, and the pulse repetition rate are fixed at apredetermined level to provide optimum performance under selectedoperating conditions. For example, the voltage pulse can have theduration D_(P) of about 1000 ns, which voltage pulse is repeated with aperiod of 1/f. The duration D_(P) of the voltage pulse and the frequencyf of the voltage pulse are chosen such that the reactance of inductorsin the voltage inverter 31 present a high impedance to the voltagepulser 60, which high impedance allows a high voltage to be developedacross the electrodes 101 a, 101 b (shown in FIG. 1) of the solar panels10 and not be shorted out by the inverter 31.

Additionally, series inductors (not shown) can be placed at the input ofthe inverter 31, which series inductors are capable of handling thecurrent input to the inverter 31 and act as an RF choke such that thevoltage pulses are not attenuated (or effectively shorted) by theresistive component of the inverter 31. The duty cycle (time the pulseis on/time the pulse is off) can be nominally 0.1-10%.

The strength of the electric field 250 imposed on the photovoltaicdevice 200 is a function of the construction of the photovoltaic device200, such as the thickness of the photovoltaic device 200, the materialand dielectric constant of the photovoltaic device 200, the maximumbreakdown voltage of the photovoltaic device 200, and so on.

As previously discussed, the photovoltaic device 200 can include anynumber of solar cells 100 and/or solar panels 10, each solar cell 100and solar panel 10, for example, being coupled in parallel, series,and/or a combination thereof. In some embodiments, imposing the electricfield 250 on a selected photovoltaic device 200 can account for thevariations in configuration of the photovoltaic device 200.

For each installation option discussed with reference to FIGS. 2A-D, thesolar cell management system 300 can apply the external voltage V_(App)to the photovoltaic device 200. For example, using the switch 55 of FIG.4, the solar cell management system 300 also can apply the externalvoltage V_(App) to the solar panels 10 that are connected in series(shown in FIG. 2B) and both series and parallel (shown in FIG. 2C).Turning to FIG. 6, the solar panels 10 are wired in series and connectedto the switch 55, such as the single pole, double throw (or three-way)switch of FIG. 4. In one embodiment, the switch 55 is also coupled tothe voltage source 50 and the external load R_(L) (e.g., shown as theinverter 31).

In FIG. 6, the electric field 250 (shown in FIG. 3) applied across eachsolar panel 10 must be greater than a predetermined minimum electricfield E_(min). Accordingly, the applied external voltage V_(App) appliedto each solar panel 10 must be greater than a predetermined minimumapplied voltage V_(min). In some embodiments, the external voltageV_(App) applied to each solar panel 10 must also be less than a maximumapplied voltage V_(max) to avoid a voltage breakdown and damage to thesolar panel 10 or, at least, damage to one or more solar cells 100 ofthe solar panels 10. Stated in another way, Equation 1 represents theupper and lower bounds of the applied external voltage V_(App).

V _(max) >V _(APP) >V _(min) >kV _(P),  (Equation 1)

In Equation 1, V_(P) is the voltage output of the solar panel 10, and kis the kth panel in the configuration. As long the relationship amongthe applied external voltage V_(App) and the minimum/maximum appliedvoltages of Equation 1 holds true, the switch 55 can the effectivelyapply the electric field 250 across each solar panel 10.

FIG. 7 illustrates the external voltage V_(App) relative to the voltagemeasured across each successive solar panel 10 (e.g., from node A acrossnodes B, C . . . N) shown in FIG. 6 while the switch 55 is in the secondposition. As shown in FIG. 7, the voltage across each solar panel 10increases by the voltage output of the solar panel 10. For example, eachsolar panel 10 generates a voltage of approximately twenty-four voltsand that a voltage measured between the node A and any measurement nodeis approximately k×24 Volts, where k is the number of the solar panels10 across which the voltage is being measured. If the inequality of theEquation 1 cannot be satisfied, the embodiment shown in FIG. 6 can bemodified to include additional switches 55. For example, in oneembodiment, a second switch 55 (switch 55 b) can be coupled into theseries of the solar panels 10 as shown in FIG. 8. However, more than oneswitch 55 (i.e., switch 55 a, 55 b . . . 55 n) can be coupled to thesolar panels 10 as desired.

Turning to FIG. 8, a toggle switch 72 can be added between the voltagesource 50 and each group of k solar panels 10. To simplify the figuresand for illustration purposes only, interconnections between differentpoints in FIG. 8 are designated by the bordered capital letters A and B,where A couples to A and B couples to B. The toggle switch 72 canrepresent a single-pole, single throw (two-way) switch. Specifically,the toggle switch 72 can include N input ports and 1 output port. Thetoggle switch 72 further defines an ON state and an OFF state. In the ONstate, all of the N input ports are simultaneously connected to thesingle output port. In the OFF state, none of the input ports areconnected to the single output port. The toggle switch 72 can beactivated by the switch controller 45, which also controls the switches55 a, 55 b, and so on. As shown in FIG. 8, the toggle switch 72 providesa return electrical path for the voltage source 50 when the switches 55a, 55 b are in the first position (as discussed with reference to FIG.4). The toggle switch 72 is activated (the ON state) when the switches55 a, 55 are connected to the voltage source 50 and the electric field250 (shown in FIG. 3) is applied to the solar panels 10. The toggleswitch 72 deactivates (the OFF state) while the solar panels 10 areproviding power to the inverter 31.

In a preferred embodiment, the switch control 45 can be synchronizedsuch that switches 55 a, 55 b are placed in a first positionsimultaneously and connected to the voltage source 50, while the toggleswitch 72 is concurrently activated in the ON state. Likewise, theswitch controller 45 simultaneously places the switches 55 a, 55 b inthe second position and also deactivates the toggle switch 72 (the OFFstate). In some embodiments, an energy storage device—such as thecapacitor 41, the inductor 42, and/or the battery 43—can be placedbefore the inverter 31 to mitigate any voltage drop-out being seen bythe inverter 31 while the switches 55 a, 55 b are in the first position.

As discussed with reference to FIG. 4, the solar cell management system300 also can apply the external voltage V_(App) to the solar panels 10that are connected in parallel. Turning to FIG. 9, more than one switch55 can be controlled by the switch controller 45. In a preferredembodiment, each of the switches 55 a, 55 b can be synchronized by theswitch controller 45 and are connected and disconnected simultaneously.As before an energy storage device—such as the capacitor 41, theinductor 42, and/or the battery 43—can be placed before the inverter 31to mitigate any voltage drop-out being seen by the inverter 31 while theswitches 55 a, 55 b are in the first position.

Using the switch 55 of FIG. 4, the solar cell management system 300 alsocan apply the external voltage V_(App) to the solar panels 10 that areconnected in both series and parallel (shown in FIG. 2C). Turning toFIG. 10, two or more of the solar panels 10 are shown to be wired inseries. The series wired solar panels 10 are then interconnected inparallel. The number of the solar panels 10 that are wired in series andin parallel can be preselected as desired.

As shown in FIG. 10, one or more switches 55 can be used to apply theelectric field 250 (shown in FIG. 3) across the solar panels 10. If morethan one switch 55 is used, the solar panels 10 can be wired as shown inFIG. 11. Turning to FIG. 11, the series wired solar panels 10 are wiredin parallel and then interconnected to the switches 55 a, 55 b. In apreferred embodiment, the switch controller 45 synchronizes the switches55 a, 55 b to be disconnected from the inverter 31 simultaneously.Similarly, the switch controller 45 connects both the switches 55 a, 55b to the voltage source 50 at the same time. In some embodiments, anenergy storage device—such as the capacitor 41, the inductor 42, and/orthe battery 43—can be placed before the inverter 31 to mitigate anyvoltage drop-out being seen by the inverter 31 while the switches 55 a,55 b are in the first position.

In yet another embodiment, the solar cell management system 300 cancooperate with the solar panels typically found in many residentialinstallations—where each of the solar panels 10 are connected to its owninverter 31 (shown in FIG. 2D). Turning to FIGS. 12A-B, the switch 55can cooperate with each solar panel 10 in a number of ways. In oneembodiment, FIG. 12A illustrates the switch 55, the voltage source 50,and the switch controller 45 integrated into the inverter 31. Becausethe inverter 31 is typically connected to a power source, the capacitor41 can be placed within the inverter 31. Alternatively, as shown in FIG.2D, multiple solar panels 10 are typically used in combination and eachare coupled to its own inverter 31 such that the capacitor 41 is notused. In some embodiments, each inverter 31 operates independently ofall other inverters 31 such that the switch 55 is not synchronizedbetween inverters 31. Accordingly, a momentary drop out of power on aselected solar panel does not appreciably affect the quality of powerfrom the plurality of solar panels 10 and inverters 31.

The embodiment shown in FIG. 12A advantageously can be targeted at anynew solar panel deployment. In an alternative embodiment with referenceto FIG. 12B, each solar panel 10 and inverter 31 pair can include itsown switch 55 a-55 n. Each switch 55 is connected to a central switch46, which is controlled by a switch controller 72, and the voltagesource 50.

The central switch 46 can provide two concurrent outputs to each solarpanel 10, each switch 55, and each inverter 31. The first output fromthe central switch 46 includes A1, B1 . . . N1 and activates each switch55 into the first position as discussed with reference to FIG. 4. Theexternal voltage V_(APP) is applied from the voltage source 50 throughthe second output of the central switch 46, which includes A2, B2 . . .N2.

The switch controller 72 activates a selected switch 55, one at a time,through the central switch 46 and applies the external voltage V_(APP)from the voltage source 50 to each of the solar panel 10 and inverter 31pairs, serially. Since the duty cycle of each individual switch 55 islow—typically less than 2%—the switch controller 72 controls and drivesa large number of switches 55, solar panels 10, and inverters 31.

There is no limitation on this embodiment that would preclude the switchcontroller 72 from switching and connecting the voltage source 50 tomultiple solar panels 10 as long as the voltage applied to each panel isgreater than the V_(min). In an alternative embodiment, more than oneswitch controller 72 can be added, with each switch controller 72 beingresponsible for a predetermined number of the solar panels 10. Each ofthe switch controllers 72 can behave independently.

As discussed above with reference to FIG. 5, the solar cell managementsystem 300 can also apply the external voltage V_(App) to thephotovoltaic device 200 using the voltage pulser 60 for a number ofconfigurations of the solar panels 10. Turning to FIG. 13, the voltagepulser circuit 60 is connected to the solar panels 10 wired in series.As was discussed above, as long as the inequality in Equation 1 issatisfied, the voltage pulser 60 behaves as shown in FIG. 14. FIG. 14illustrates the external voltage V_(App) relative to the voltage acrosseach successive solar panel 10 (measured across the node A to each ofthe solar panels 10 at the nodes B, C . . . N) in the series. As shownin FIG. 14, the voltage at each solar panel 10 increases by the voltageoutput of the solar panel 10. For example, each solar panel 10 generatesa voltage of approximately twenty-four volts and that a voltage measuredacross any solar panel 10 (from the node A to the node B, C . . . N) isapproximately k×24 Volts, where k is the number of solar panels 10across which the voltage is being measured. If the inequality of theEquation 1 cannot be satisfied, the embodiment shown in FIG. 13 can bemodified to include additional voltage pulsers 60.

With reference to FIG. 5, to maximize the strength of the electric field250 across the set of solar cells 100 or the solar panels 10, the solarmanagement system 300 considers the DC voltage being generated by eachof the solar cells 100 or the solar panels 10 themselves. In oneembodiment, a high voltage uplift circuit, such as an Uplift InjectorCircuit 90 (shown in FIG. 18), can be used with the voltage pulser 60 tosuperimpose a voltage pulse on top of the DC voltage of the solar panels10 themselves. This superposition of the voltage pulse from the voltagepulser 60 on top of the DC voltage generated by solar panels 10 can bedone by creating a negative reference for the injected high voltagepulse signal that is equal to the positive DC voltage delivered by solarpanels 10.

Turning to FIG. 18, the Uplift Injector Circuit 90 includes a capacitor91, working in concert with an inductor 92, allows the capacitor 91 tohold a charge equal to the voltage delivered by the solar panels 10. Thecapacitor 91 and the inductor 92 creates an uplifted negative referencefor the injected high voltage pulse signal which is connected to thevoltage pulser 60 through capacitors 94 and 95. The positive referencefrom the voltage pulser 60 is connected through a diode 93, whichprovides reverse bias protection to the positive voltage line connectedto the interface that connects to the solar panels 10 and the interfacewhich is connected to the inverter 31. To provide RF isolation so thatvoltage pulses from the voltage pulser 60 are not shorted out by theinverter 31 and to additionally provide RF isolation between the othersolar panels 10 connected between the Uplift Injector Circuit 90 90 andthe inverter 31, inductors 96 and 97 can be placed in series between theinverter 31 and the voltage pulser 60 to provide a RF choke for any highvoltage pulses. The inductors 96 and 97 attenuate any voltage pulse fromthe voltage pulser 60 passing across them and isolate the voltage pulser60 from the remainder of the circuit towards the inverter 31.

As shown in FIG. 18, the inductor 92 provides high reactance protectionto the injected high voltage pulse signal, keeping the signal fromfeeding back into the capacitor 91. The result is the injected highvoltage pulse signal sitting on top of the DC voltage delivered by thesolar panels 10 and rising and falling with the DC voltage, therebymaximizing the voltage pulse.

In a preferred embodiment, the Uplift Injector Circuit 90 can beincorporated as part of an interface between each voltage pulser 60 anda number of solar panels 10.

In some embodiments, more than one voltage pulser 60 can be used for apredetermined number of solar panels 10 as shown in FIG. 15A. Turning toFIG. 15A, the solar panels 10 are arranged in both in series and inparallel and interconnected with the voltage pulsers 60. Each voltagepulser 60 is responsible for k panels and interconnected to the inverter31. In some embodiments, similar to the switching system previouslydescribed in FIGS. 6 and 8-11, the use of more than one voltage pulser60 can be synchronized. However, in the embodiment shown in FIG. 15A,the use of more than one voltage pulser 60 advantageously does notrequire synchronization between different voltage pulsers 60. Becausethe voltage pulse from each voltage pulser 60 is local to a set of thesolar panels 10 that are interconnected, the application of the voltagepulse does not affect the output of the inverter 31.

Another embodiment of implementing multiple voltage pulsers for thesolar panels 10 wired in series is shown in FIG. 15B. Turning to FIG.15B, the voltage pulser 60 is connected to each solar panel 10 via aserial switch 70. The serial switch 70 can include N output ports forcoupling k solar panels 10 as shown in FIG. 15B. In the embodiment shownin FIG. 15B, to simplify the figures and for illustration purposes only,interconnections between different points in the circuit are designatedby the capital letters A1 and B1 with A1 connecting to A1 and B1connecting to B1 and so on.

The serial switch 70 includes one input port connected to the voltagepulser 60. The N output ports of the serial switch 70 connect thevoltage pulser 60 across k panels 10 at a time. In one example, theserial switch 70 connects the voltage pulser 60 to the output ports A1and A2. The voltage pulser 60 applies the external voltage V_(App)across the solar panels 1 through k. The serial switch 70 disconnectsthe voltage pulser 60 from the outputs A1 and A2 and connects thevoltage pulser 60 to outputs B1 and B2. When activated, the voltagepulser 60 applies the voltage pulse V_(App) across the k panels in thatleg of the solar panels 10 wired in series. In a similar manner, theserial switch 70 cycles through all ports applying the voltage pulseV_(App) to k panels at a time. After all of the n solar panels 10 inseries have had a voltage pulse V_(App) applied, the serial switch 70reconnects to leads A1 and A2 and the process repeats. In this manner, asingle voltage pulser 60 can be utilized to apply voltage pulses V_(App)to a large number of solar panels 10. Because the duty cycle of thevoltage pulse is low—typically less than 2%—a single voltage pulser 60can control multiple solar panels 10.

Turning to FIG. 16, the voltage pulser 60 cooperates with the solarpanels 10 wired in both series and parallel in the manner discussedabove with reference to FIG. 2C. The voltage pulser 60 is connectedacross the 2 k solar panels 10 and the inverter 31. For most situations,the magnitude of the series and shunt resistances (>>1 MΩ) found in mostsolar panels 10 allow the voltage pulser 60 to cooperate with a largenumber of solar panels 10.

FIGS. 17A and 17B illustrates the voltage pulser 60 cooperating with thetypical, residential installations of a solar panel 10. In oneembodiment, turning to FIG. 17A, the voltage pulser 60 is integratedinto the inverter 31 connected across solar panel 10.

FIG. 17B illustrates an alternate embodiment for cooperating with thetypical, residential installations of a solar panel 10 and includes eachsolar panel 10 and the inverter 31 connected via the serial switch 70 toa central voltage pulser 60. The central voltage pulser 60 applies thevoltage pulse V_(App) through the serial switch 70 and serially to eachof the solar panels 10. The serial switch 70 in FIG. 17B is shown as anN×1 switch. The serial switch 70 has one input port, which is connectedto the voltage pulser 60, and N output ports, which are connected acrosseach individual solar panel 10 as shown in FIG. 17B. The serial switch70 connects voltage pulser 60 across each panel 10 one at a time.

In one example, the serial switch 70 connects the voltage pulser 60 tothe output ports A1 and A2. When activated, the voltage pulser 60applies the voltage pulse V_(App) across a selected solar panel 10coupled to the serial switch 70. The serial switch 70 then disconnectsthe voltage pulser 60 from the output ports A1 and A2 and connects thevoltage pulser 60 to the output ports B1 and B2. Again, when activated,the voltage pulser 60 applies the voltage pulse V_(App) across anotherselected solar panel 10 coupled to the serial switch 70. In a likemanner, the serial switch 70 cycles through all active ports applying avoltage pulse V_(App) to a selected solar panel 10 at a time. After allof the n solar panels 10 have had a voltage pulse V_(App) applied, theserial switch 70 reconnects to the output ports A1 and A2, and theprocess repeats. In this manner, a single voltage pulser 60 can beutilized to apply voltage pulses V_(App) to a large number of solarpanels 10. Since the duty cycle of the voltage pulses is very low,typically less than 2%, a single voltage pulser 60 can control a largenumber of the solar panels 10 and inverters 31.

There is no limitation on this embodiment that would preclude thecentral high voltage pulse generator from switching a voltage pulse tomultiple solar panels concurrently as long as the voltage applied toeach panel is greater than V_(min). While the option exists to apply ahigh voltage pulse switch to multiple solar panels 10 concurrently, thepreferred embodiment includes a single voltage pulser 60 for switchingbetween the solar panels 10, such as in serial. In the event that thenumber of the solar panels 10 becomes large, additional voltage pulsers60 and serial switches 70 can be added, with each voltage pulser 60responsible for a number of solar panels 10.

The described embodiments are susceptible to various modifications andalternative forms, and specific examples thereof have been shown by wayof example in the drawings and are herein described in detail. It shouldbe understood, however, that the described embodiments are not to belimited to the particular forms or methods disclosed, but to thecontrary, the present disclosure is to cover all modifications,equivalents, and alternatives.

What is claimed is:
 1. A system for increasing photovoltaic deviceefficiency, comprising: a voltage source circuit for supplying a voltagesignal; and a switching circuit having a first port for coupling withsaid voltage source circuit and a second port for coupling with aphotovoltaic device and being configured to apply a time varying voltagesignal to the photovoltaic device by alternating between a first modefor providing the supplied voltage signal to the photovoltaic device anda second mode for suspending the supplied voltage signal from beingprovided to the photovoltaic device, wherein the time varying voltagesignal generates an electric field across the photovoltaic device forincreasing an output current or an output power produced by thephotovoltaic device.
 2. The system of claim 1, wherein said voltagesource circuit comprises a constant voltage source circuit for supplyingthe voltage signal as a constant voltage signal, a controllable voltagesource circuit for supplying the voltage signal as a controllablevoltage signal, a voltage pulser circuit for supplying the voltagesignal as a pulsed voltage signal, a periodic voltage source circuit forsupplying the voltage signal as a periodic voltage signal or acombination thereof.
 3. The system of claim 1, further comprising acontrol circuit for adjusting a frequency of the time varying voltagesignal, a magnitude of the time varying voltage signal, a period of thetime varying voltage signal, a repetition rate of the time varyingvoltage signal, a duty cycle of the time varying voltage signal, aduration of the time varying voltage signal or a combination thereof. 4.The system of claim 3, wherein said control circuit adjusts thefrequency of the time varying voltage signal to be within a frequencyrange between 20 KHz and 200 KHz, the magnitude of the time varyingvoltage signal to be within an amplitude range between 100 Volts and 500Volts, the period of the time varying voltage signal to be within aperiod range between 5 microseconds and 50 microseconds, the duty cycleof the time varying voltage signal to be within a duty cycle rangebetween 0.1% and 10%, the duration of the time varying voltage signal tobe in a duration range between 10 nanoseconds and 2000 nanoseconds or acombination thereof.
 5. The system of claim 3, wherein said controlcircuit adjusts the frequency, the magnitude, the period, the repetitionrate, the duty cycle, the duration or the combination thereof based atleast in part on the output current of the photovoltaic device, anoutput voltage of the photovoltaic device or both.
 6. The system ofclaim 3, further comprising a measuring circuit for measuring the outputcurrent of the photovoltaic device, an output voltage of thephotovoltaic device or both, wherein said control circuit adjusts thefrequency, the magnitude, the period, the repetition rate, the dutycycle, the duration or the combination thereof based at least in partupon the measured output current, the measured output voltage or both.7. The system of claim 6, wherein said measuring circuit is at leastpartially integrated with said control circuit.
 8. The system of claim6, wherein said measuring circuit includes a current sensor coupled inseries between the photovoltaic device and a load for measuring theoutput current of the photovoltaic device, a voltage probe coupledacross the photovoltaic device for measuring the output voltage of thephotovoltaic device or a combination thereof.
 9. The system of claim 3,wherein said control circuit controls the electric field, the outputcurrent, the output power or a combination thereof by adjusting the timevarying voltage signal.
 10. The system of claim 9, wherein said controlcircuit maximizes the output current of the photovoltaic device, theoutput power of the photovoltaic device or a combination thereof. 11.The system of claim 3, wherein said control circuit determines themagnitude of the time varying voltage signal based upon a deviceconfiguration of the photovoltaic device.
 12. The system of claim 3,wherein said control circuit is at least partially integrated with saidvoltage source circuit, said switching circuit or both.
 13. The systemof claim 1, wherein said switching circuit comprises at least onemechanical switch, at least one solid state switch, at least oneswitching transistor or a combination thereof.
 14. The system of claim13, wherein said switching circuit includes one or more double throwswitching circuits.
 15. The system of claim 1, wherein said switchingcircuit is at least partially integrated with said voltage sourcecircuit.
 16. The system of claim 1, wherein said switching circuit isconfigured to apply the time varying voltage signal to the photovoltaicdevice as one or more cycles of a periodic voltage signal.
 17. Thesystem of claim 16, wherein the periodic voltage signal comprises atleast one voltage pulse.
 18. The system of claim 16, wherein theperiodic voltage signal has a positive magnitude.
 19. The system ofclaim 16, wherein the cycles of the periodic voltage signal have auniform magnitude.
 20. The system of claim 16, wherein said switchingcircuit is configured to apply a plurality of sets of the one or morecycles of the periodic voltage signal to the photovoltaic device. 21.The system of claim 20, wherein said switching circuit applies a firstset of the one or more cycles of the periodic voltage signal to generatea first electric field across the photovoltaic device and subsequentlyapplies a second of the one or more cycles of the periodic voltagesignal to generate a second electric field across the photovoltaicdevice.
 22. The system of claim 21, wherein said switching circuitoperates in the second mode between application of the first set andapplication of the second set.
 23. The system of claim 20, wherein saidswitching circuit operates in the second mode between application ofadjacent sets of the one or more cycles of the periodic voltage signal.24. The system of claim 1, further comprising a control circuit foradjusting a switching frequency between the first mode and the secondmode, a first duration of the first mode, a second duration of thesecond mode, a duty cycle of the first mode and the second mode, a firstrepetition rate of the first mode, a second repetition rate of thesecond mode or a combination thereof.
 25. The system of claim 24,wherein said control circuit adjusts the switching frequency to bewithin a frequency range between 20 KHz and 200 KHz, the first durationto be in a first duration range between 10 nanoseconds and 2000nanoseconds, the second duration to be in a second duration rangebetween 10 nanoseconds and 2000 nanoseconds, the duty cycle of the timevarying voltage signal to be within a duty cycle range between 0.1% and10% or a combination thereof.
 26. The system of claim 24, wherein saidcontrol circuit is at least partially integrated with said voltagesource circuit, said switching circuit or both.
 27. The system of claim1, wherein the second port of said switching circuit is coupled with aplurality of photovoltaic devices, said switching circuit applying thetime varying voltage signal to the photovoltaic devices for generatingan electric field across the photovoltaic devices for increasing anoutput current or an output power produced by the photovoltaic devices.28. The system of claim 27, wherein the plurality of photovoltaicdevices is disposed in a parallel device configuration, a series deviceconfiguration or a combination thereof.
 29. The system of claim 1,further comprising a second switching circuit having a first port forcoupling with said voltage source circuit and a second port for couplingwith a second photovoltaic device and being configured to apply a secondtime varying voltage signal to the second photovoltaic device byalternating between a first mode for providing the supplied voltagesignal to the second photovoltaic device and a second mode forsuspending the supplied voltage signal from being provided to the secondphotovoltaic device, wherein the second time varying voltage signalgenerates a second electric field across the second photovoltaic devicefor increasing an output current or an output power produced by thesecond photovoltaic device.
 30. The system of claim 29, wherein saidsecond switching circuit is configured to apply the second time varyingvoltage signal to the second photovoltaic device concurrently with thetime varying voltage signal applied to the photovoltaic device.
 31. Thesystem of claim 29, wherein the first mode of said second switchingcircuit is synchronized with the first mode of said switching circuit,wherein the second mode of said second switching circuit is synchronizedwith the second mode of said switching circuit or both.
 32. The systemof claim 29, wherein said second switching circuit is at least partiallyintegrated with said switching circuit.
 33. The system of claim 1,further comprising: a second voltage source circuit for supplying asecond voltage signal; and a second switching circuit having a firstport for coupling with said second voltage source circuit and a secondport for coupling with a second photovoltaic device and being configuredto apply a second time varying voltage signal to the second photovoltaicdevice by alternating between a first mode for providing the suppliedsecond voltage signal to the second photovoltaic device and a secondmode for suspending the supplied second voltage signal from beingprovided to the second photovoltaic device, wherein the second timevarying voltage signal generates a second electric field across thesecond photovoltaic device for increasing an output current or an outputpower produced by the second photovoltaic device.
 34. The system ofclaim 33, wherein said second switching circuit is configured to applythe second time varying voltage signal to the second photovoltaic deviceconcurrently with the time varying voltage signal applied to thephotovoltaic device.
 35. The system of claim 33, wherein the first modeof said second switching circuit is synchronized with the first mode ofsaid switching circuit, wherein the second mode of said second switchingcircuit is synchronized with the second mode of said switching circuitor both.
 36. The system of claim 33, wherein said second voltage sourcecircuit is at least partially integrated with said voltage sourcecircuit.
 37. The system of claim 33, wherein said second switchingcircuit is at least partially integrated with said switching circuit.38. The system of claim 1, wherein the time varying voltage signal issuperimposed onto an output voltage produced by the photovoltaic device.39. The system of claim 38, further comprising an uplift circuit forsuperimposing the time varying voltage signal onto the output voltage.40. The system of claim 39, wherein said uplift circuit creates anegative reference for the time varying voltage signal.
 41. The systemof claim 39, wherein said uplift circuit is coupled between said voltagesource circuit and the photovoltaic device.
 42. The system of claim 1,wherein said switching circuit operates in the second mode for apredetermined time interval between the adjacent first modes.
 43. Thesystem of claim 42, wherein said switching circuit operates to supply novoltage from said voltage source circuit to the photovoltaic deviceduring the predetermined time interval.
 44. The system of claim 1,wherein said switching circuit is configured to apply the time varyingvoltage signal to the photovoltaic device without structuralmodification of the photovoltaic device.
 45. The system of claim 1,wherein the second port of said switching circuit is coupled with one ormore existing electrodes of the photovoltaic device.
 46. The system ofclaim 1, wherein the photovoltaic device is configured to drive a load.47. The system of claim 46, wherein the load receives the increasedoutput current or the increased output power produced by thephotovoltaic device and converts the increased output current or theincreased output power into alternating current power or current. 48.The system of claim 47, wherein the load comprises an inverter.
 49. Thesystem of claim 46, wherein the load is electrically isolated from thephotovoltaic device in the radio frequency domain.
 50. The system ofclaim 49, wherein the load is electrically isolated from thephotovoltaic device via a capacitor, an inductor, a battery or acombination thereof.
 51. The system of claim 46, further comprising anenergy storage device for mitigating voltage drop-out at the load in thefirst mode of said switching circuit.
 52. The system of claim 51,wherein said energy storage device comprises a capacitor, an inductor, abattery or a combination thereof.
 53. The system of claim 51, whereinsaid energy storage device stores the output current or the output powerproduced by the photovoltaic device in the second mode of said switchingcircuit.
 54. The system of claim 53, wherein said energy storage devicedrives the load via the stored output current or the stored output powerin the first mode of said switching circuit.
 55. The system of claim 54,further comprising a choke circuit for electrically isolating the loadfrom the photovoltaic device in the radio frequency domain as saidenergy storage device drives the load.
 56. The system of claim 55,wherein said choke circuit comprises a capacitor, an inductor, a batteryor a combination thereof.
 57. The system of claim 46, wherein the secondport of said switching circuit is configured for coupling with the loadand for providing the increased output current or the increased outputpower to the load in the first mode and in the second mode.
 58. Thesystem of claim 46, wherein said switching circuit has a third port forcoupling with the load and for providing the increased output current orthe increased output power to the load in the second mode.
 59. Thesystem of claim 58, wherein said switching circuit closes a firstcurrent path between the first port and the second port and opens asecond current path between the second port and the third port in thefirst mode and opens the first current path and closes the secondcurrent path in the second mode.
 60. The system of claim 1, wherein saidswitching circuit closes a current path between the first port and thesecond port in the first mode and opens the current path in the secondmode.
 61. The system of claim 1, wherein the time varying voltage signalgenerates the electric field with a predetermined field direction acrossthe photovoltaic device.
 62. The system of claim 61, wherein thepredetermined field direction is in the same direction as a polarity ofthe photovoltaic device to increase the output current or the outputpower produced by the photovoltaic device or the predetermined fielddirection is in an opposite direction as the polarity of thephotovoltaic device to decrease the output current or the output powerproduced by the photovoltaic device.
 63. The system of claim 1, whereinsaid switching circuit enables said voltage source circuit for supplyingthe voltage signal in the first mode and disables said voltage sourcecircuit from supplying the voltage signal in the second mode.
 64. Thesystem of claim 1, wherein the photovoltaic device comprises a solarcell, an array of solar cells, a solar panel, an array of solar panelsor a combination thereof.
 65. The system of claim 1, wherein generationof the electric field increases the output current or the output powerproduced by the photovoltaic device by up to fifty percent under lowlight conditions.
 66. The system of claim 1, wherein generation of theelectric field increases the output current or the output power producedby the photovoltaic device by more than fifty percent under low lightconditions.
 67. The system of claim 1, wherein generation of theelectric field increases the output current or the output power producedby the photovoltaic device by up to twenty percent under high intensitylight conditions.
 68. The system of claim 1, wherein generation of theelectric field increases the output current or the output power producedby the photovoltaic device between twenty percent and fifty percent. 69.The system of claim 1, wherein generation of the electric fieldincreases the output current or the output power produced by thephotovoltaic device by more than fifty percent.
 70. The system of claim1, wherein the increase in the output current or the output powerproduced by the photovoltaic device is based upon an intensity of lightincident on the photovoltaic device, a thickness of the photovoltaicdevice, a signal width of the time varying voltage signal, a signalfrequency of the time varying voltage signal, or a combination thereof.71. A method for increasing photovoltaic device efficiency, comprising:providing a voltage source circuit for supplying a voltage signal; andcoupling a first port of a switching circuit with the voltage sourcecircuit, the switching circuit having a second port for coupling with aphotovoltaic device and being configured to apply a time varying voltagesignal to the photovoltaic device by alternating between a first modefor providing the supplied voltage signal to the photovoltaic device anda second mode for suspending the supplied voltage signal from beingprovided to the photovoltaic device, wherein the time varying voltagesignal generates an electric field across the photovoltaic device forincreasing an output current or an output power produced by thephotovoltaic device.
 72. The method of claim 71, wherein the second portof the switching circuit is configured for coupling with a load, theincreased output current or the increased output power being provided tothe load in the first mode and in the second mode.
 73. The method ofclaim 71, wherein the switching circuit has a third port for couplingwith a load and for providing the increased output current or theincreased output power to the load in the second mode.
 74. A method forincreasing photovoltaic device efficiency, comprising: coupling a firstport of a switching circuit with a photovoltaic device, the switchingcircuit having a second port for coupling with a voltage source circuitfor supplying a voltage signal and being configured to apply a timevarying voltage signal to the photovoltaic device by alternating betweena first mode for providing the supplied voltage signal to thephotovoltaic device and a second mode for suspending the suppliedvoltage signal from being provided to the photovoltaic device, whereinthe time varying voltage signal generates an electric field across thephotovoltaic device for increasing an output current or an output powerproduced by the photovoltaic device.
 75. The method of claim 74, furthercomprising coupling the first port with a load, the increased outputcurrent or the increased output power being provided to the load in thefirst mode and in the second mode.
 76. The method of claim 74, furthercomprising coupling a third port of the switching circuit with a load,the switching circuit being configured for providing the increasedoutput current or the increased output power to the load via the thirdport in the second mode.